[Elecraft] OT: Astron linear PS regulation issues

[hbjr at optilink.us]

Filter caps bad?  AC on the DC supply side maybe?  A well made linear supply
does not make noise that has to be filtered otherwise.  All switching
supplies must be cleaned up because their design generates noise.

-----Original Message-----
From: elecraft-bounces at mailman.qth.net <elecraft-bounces at mailman.qth.net> On
Behalf Of K9MA
Sent: Monday, February 25, 2019 8:13 PM
To: elecraft at mailman.qth.net
Subject: Re: [Elecraft] OT: Astron linear PS regulation issues

That's interesting. About the only way I know that a linear supply can be
noisy is if the regulator oscillates. That can easily happen. Most of them
use emitter followers, which are often unstable driving a capacitive load.
That's usually easy to fix by inserting a small inductance between the
emitter of the transistor and the load. A few turns of the appropriate sized
wire around a ferrite bead usually works.

73,
Scott K9MA

On 2/25/2019 18:57, William Rascher wrote:
> On Monday, February 25, 2019 4:26:40 PM CST Rose wrote:
>> I've found instances of regulation failures caused by loose hardware.
> With the RS-35m Astron Linear PS I have issues with noise.  I 
> purchased the PS because everyone around me swears that they are 
> great.  Well, from my experience the Powerwerx SS-30DV is far cleaner, 
> quieter, and fewer $$.  I though the problem was something along the line
of LED lighting, in my
> shack was generating the  noise.   When I used a battery for the PX3 & KX3
> in my shack during a power outage the PX3 screen was so clear I was
> stunned.    I have 3 different Astron linear PS and all are noisy.


--
Scott  K9MA

k9ma at sdellington.us

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